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Scientific Fields (scientific + field)
Selected AbstractsToxicogenomics: a pivotal piece in the puzzle of toxicological researchJOURNAL OF APPLIED TOXICOLOGY, Issue 4 2007Elisavet T. Gatzidou Abstract Toxicogenomics, resulting from the merge of conventional toxicology with functional genomics, being the scientific field studying the complex interactions between the cellular genome, toxic agents in the environment, organ dysfunction and disease state. When an organism is exposed to a toxic agent the cells respond by altering the pattern of gene expression. Genes are transcribed into mRNA, which in turn is translated into proteins that serve in a variety of cellular functions. Toxicogenomics through microarray technology, offers large-scale detection and quantification of mRNA transcripts, related to alterations in mRNA stability or gene regulation. This may prove advantageous in toxicological research. In the present review, the applications of toxicogenomics, especially to mechanistic and predictive toxicology are reported. The limitations arising from the use of this technology are also discussed. Additionally, a brief report of other approaches, using other -omic technologies (proteomics and metabonomics) that overcome limitations and give global information related to toxicity, is included. Copyright © 2007 John Wiley & Sons, Ltd. [source] Cooperation and conflict in host,microbe relationsAPMIS, Issue 5-6 2009ELLING ULVESTAD Hosts and microbes associate in a variety of relations along a continuum ranging from symbiotic to pathogenic. Defence mechanisms have been evolutionarily selected in both hosts and microbes to protect the organism's integrity. Such defences have to be utilized with caution. They must be adapted to the tasks at hand; otherwise any symbiotic relation would be impossible. To explain this cautionary use of defences we need to understand how life on Earth evolved into cooperative and competing entities at various levels of organization. The purpose of this article is to review theory and selected mechanisms relating to the evolution and development of host,microbe interactions, with special emphasis on host responses. The rationale is that without theory, extrapolations from misleading observations can dominate and distort, for a significant time, the course of a scientific field. The argument is set forth that social evolution theory provides a conceptual framework for addressing questions relating to interaction between hosts and microbes. The article is a partial summary of arguments presented in my book Defending life , the nature of host,parasite relations. [source] Uses and abuses of fractal methodology in ecologyECOLOGY LETTERS, Issue 3 2004J. M. Halley Abstract Fractals have found widespread application in a range of scientific fields, including ecology. This rapid growth has produced substantial new insights, but has also spawned confusion and a host of methodological problems. In this paper, we review the value of fractal methods, in particular for applications to spatial ecology, and outline potential pitfalls. Methods for measuring fractals in nature and generating fractal patterns for use in modelling are surveyed. We stress the limitations and the strengths of fractal models. Strictly speaking, no ecological pattern can be truly fractal, but fractal methods may nonetheless provide the most efficient tool available for describing and predicting ecological patterns at multiple scales. [source] EPPO database on diagnostic expertise: http://dc.eppo.orgEPPO BULLETIN, Issue 1 2010A. S. Roy In 2004, the EPPO Council expressed profound concerns about the decreasing expertise in plant protection and declared a state of emergency for Plant Health (,Madeira declaration'). As diagnostics is one of the scientific fields which are vital for sustaining sound plant health policies, a questionnaire was launched and all EPPO member countries were asked to provide information about their diagnostic expertise, focusing on regulated pests or pests which may present a risk to the EPPO region. In 2006, results of the questionnaire were analysed and compiled by the EPPO Secretariat into a new database. This database now contains detailed information (contact addresses, quality programmes, and accreditations) for 80 diagnostic laboratories from 28 EPPO member countries. More than 500 experts are now registered with details about their diagnostic expertise (pests diagnosed and methods used). The EPPO database on diagnostic expertise can be freely accessed on the Internet: http://dc.eppo.org. [source] Missing links: Eugène Dubois and the origins of paleoanthropologyEVOLUTIONARY ANTHROPOLOGY, Issue 3 2002Pat Shipman Abstract Examining the origins of various scientific fields may help to identify particular individuals whose thought, work, and discoveries have had a disproportionately large influence. Such individuals seem to serve as catalysts for a wider set of intellectual reactions, which then give rise to an entire field of study. In this paper, we propose explicit criteria for recognizing the founders of new fields. We contend that Eugène Dubois, best known as the man who found the "missing link" between apes and humans, should be recognized as one of the founding fathers of paleoanthropology. [source] The rhetoric of conference presentation introductions: context, argument and interactionINTERNATIONAL JOURNAL OF APPLIED LINGUISTICS, Issue 1 2005Elizabeth Rowley-Jolivet The process of socialisation into the academic discourse community involves acquiring mastery of its established genres. While written academic genres have been intensively studied, spoken genres are relatively under-researched. This study focuses on one such spoken research genre, the scientific conference presentation (CP) in English, and specifically on the introduction section, a sub-genre which often poses particular problems for presenters. A move analysis of the CP introductions shows that their rhetorical structure is markedly different from that of the research article, and that these differences are closely related to the contextual and epistemological characteristics of the genre. The interpersonal relations set up by the allocation of speaker and addressee roles through the use of personal pronouns are also discussed. Through a contrastive analysis of the CP introductions and those of the corresponding proceedings papers, the article examines how speakers facilitate information processing and create rapport with the audience. The data comprise video recordings of 44 CPs from 3 scientific fields (geology, medicine, and physics) and a smaller corpus of 13 corresponding articles from the physics conference proceedings. [source] The effect of misclassification on the estimation of association: a reviewINTERNATIONAL JOURNAL OF METHODS IN PSYCHIATRIC RESEARCH, Issue 2 2005Michael Höfler Abstract Misclassification, the erroneous measurement of one or several categorical variables, is a major concern in many scientific fields and particularly in psychiatric research. Even in rather simple scenarios, unless the misclassification probabilities are very small, a major bias can arise in estimating the degree of association assessed with common measures like the risk ratio and the odds ratio. Only in very special cases , for example, if misclassification takes place solely in one of two binary variables and is independent of the other variable (,non-differential misclassification') , is it guaranteed that the estimates are biased towards the null value (which is 1 for the risk ratio and the odds ratio). Furthermore, misclassification, if ignored, usually leads to confidence intervals that are too narrow. This paper reviews consequences of misclassification. A numerical example demonstrates the problem's magnitude for the estimation of the risk ratio in the easy case where misclassification takes place in the exposure variable, but not in the outcome. Moreover, uncertainty about misclassification can broaden the confidence intervals dramatically. The best way to overcome misclassification is to avoid it by design, but some statistical methods are useful for reducing bias if misclassification cannot be avoided. Copyright © 2005 Whurr Publishers Ltd. [source] Migration and other Modes of Transnationalism: Towards Conceptual Cross-FertilizationINTERNATIONAL MIGRATION REVIEW, Issue 3 2003Steven Vertovec Sociological notions such as social network, social capital and embeddedness have proven valuable when adopted into a wide variety of social scientific fields. This has certainly been the case in the sociology of migration. Similarly, certain concepts drawn from studies on different modes of transnationalism - for instance, research and theory concerning the global activities of social movements and business networks - might serve as useful tools for understanding transnational social forms and practices among migrant groups. [source] The application of Memory-Work in consumer researchJOURNAL OF CONSUMER BEHAVIOUR, Issue 1 2009Thyra Uth Thomsen Memory-Work is by origin a feminist, social constructionist method devoted to the investigation of socially constructed and culturally embedded phenomena. In this paper, Memory-Work is presented to consumer research in order to (1) widen the methodological scope of interpretive consumer research and thus advance new insights, (2) present a method well known to other scientific fields that may supplement micro-social studies of consumer's practices with more macro-cultural insights, and finally (3) to illustrate the application of the general method to the study of consumer behaviour. Apart from a few notable exceptions, Memory-Work has not yet been applied to consumer research and its benefits for this kind of research have not been discussed. This paper seeks to fill this gap, by illustrating how consumer research may apply and benefit from Memory-Work. Copyright © 2009 John Wiley & Sons, Ltd. [source] Weighted hybrid clustering by combining text mining and bibliometrics on a large-scale journal databaseJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 6 2010Xinhai Liu We propose a new hybrid clustering framework to incorporate text mining with bibliometrics in journal set analysis. The framework integrates two different approaches: clustering ensemble and kernel-fusion clustering. To improve the flexibility and the efficiency of processing large-scale data, we propose an information-based weighting scheme to leverage the effect of multiple data sources in hybrid clustering. Three different algorithms are extended by the proposed weighting scheme and they are employed on a large journal set retrieved from the Web of Science (WoS) database. The clustering performance of the proposed algorithms is systematically evaluated using multiple evaluation methods, and they were cross-compared with alternative methods. Experimental results demonstrate that the proposed weighted hybrid clustering strategy is superior to other methods in clustering performance and efficiency. The proposed approach also provides a more refined structural mapping of journal sets, which is useful for monitoring and detecting new trends in different scientific fields. [source] Understanding information related fields: A conceptual frameworkJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 13 2007Ping Zhang Many scientific fields share common interests for research and education. Yet, very often, these fields do not communicate to each other and are unaware of the work in other fields. Understanding the commonalities and differences among related fields can broaden our understanding of the interested phenomena from various perspectives, better utilize resources, enhance collaboration, and eventually move the related fields forward together. In this article, we present a conceptual framework, namely the Information-Model or I-model, to describe various aspects of information related fields. We consider this a timely effort in light of the evolutions of several information related fields and a set of questions related to the identities of these fields. It is especially timely in defining the newly formed Information Field from a community of twenty some information schools. We posit that the information related fields are built on a number of other fields but with their own unique foci and concerns. That is, core components from other fundamental fields interact and integrate with each other to form dynamic and interesting information related fields that all have to do with information, technology, people, and organization/society. The conceptual framework can have a number of uses. Besides providing a unified view of these related fields, it can be used to examine old case studies, recent research projects, educational programs and curricula concerns, as well as to illustrate the commonalities and differences with the information related fields. [source] The place of serials in referencing practices: Comparing natural sciences and engineering with social sciences and humanitiesJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 8 2006Vincent Larivière Journal articles constitute the core documents for the diffusion of knowledge in the natural sciences. It has been argued that the same is not true for the social sciences and humanities where knowledge is more often disseminated in monographs that are not indexed in the journal-based databases used for bibliometric analysis. Previous studies have made only partial assessments of the role played by both serials and other types of literature. The importance of journal literature in the various scientific fields has therefore not been systematically characterized. The authors address this issue by providing a systematic measurement of the role played by journal literature in the building of knowledge in both the natural sciences and engineering and the social sciences and humanities. Using citation data from the CD-ROM versions of the Science Citation Index (SCI), Social Science Citation Index (SSCI), and Arts and Humanities Citation Index (AHCI) databases from 1981 to 2000 (Thomson ISI, Philadelphia, PA), the authors quantify the share of citations to both serials and other types of literature. Variations in time and between fields are also analyzed. The results show that journal literature is increasingly important in the natural and social sciences, but that its role in the humanities is stagnant and has even tended to diminish slightly in the 1990s. Journal literature accounts for less than 50% of the citations in several disciplines of the social sciences and humanities; hence, special care should be used when using bibliometric indicators that rely only on journal literature. [source] A multi-ontology framework to guide agriculture and food towards diet and healthJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 8 2007Matthew C Lange Abstract Global increases in metabolic diseases that can be influenced by diet have re-emphasized the importance of considering how different foods can improve human health. The entire agricultural enterprise has an unprecedented opportunity to increase its value by producing foods that improve the health of consumers. Research efforts in agriculture/food science/nutrition are endeavoring to do so, although little tangible success has been achieved. At the core of the problem is a failure to define the goal itself: health. Health, as a scientifically measurable concept, is poorly defined relative to disease, and yet consensus-based, curated vocabularies that describe the multiple variations in human health in useful terms are critical to unifying the scientific fields related to agriculture and nutrition. Each of the life-science disciplines relating to health has developed databases, thesauri, and/or ontologies to capture such knowledge. High-throughput and -omic technologies are expanding both the amount and heterogeneity of available information. Unfortunately, the language used to describe substantially similar (even logically equivalent) concepts is often different between information systems. Increasing the future value of agriculture, therefore, will depend on creating a process for generating common ontologies of the concept of health, and guiding the development of a common language. This paper illustrates a framework for integrating heterogeneous ontologies into interdisciplinary, foods-for-health knowledge systems. A common system of language that describes health and is shared by all the life-science disciplines will provide immediate benefits in terms of increased health-claim regulatory efficiencies and predictive functions for individualized diets. Ultimately, these vocabularies will guide agriculture to its next goal of producing health-enhancing foods. Copyright © 2007 Society of Chemical Industry [source] ON AXISYMMETRIC TRAVELING WAVES AND RADIAL SOLUTIONS OF SEMI-LINEAR ELLIPTIC EQUATIONSNATURAL RESOURCE MODELING, Issue 3 2000THOMAS P. WITELSKI ABSTRACT. Combining analytical techniques from perturbation methods and dynamical systems theory, we present an elementaryapproach to the detailed construction of axisymmetric diffusive interfaces in semi-linear elliptic equations. Solutions of the resulting non-autonomous radial differential equations can be expressed in terms of a slowlyvarying phase plane system. Special analytical results for the phase plane system are used to produce closed-form solutions for the asymptotic forms of the curved front solutions. These axisym-metric solutions are fundamental examples of more general curved fronts that arise in a wide variety of scientific fields, and we extensivelydiscuss a number of them, with a particular emphasis on connections to geometric models for the motion of interfaces. Related classical results for traveling waves in one-dimensional problems are also reviewed briefly. Manyof the results contained in this article are known, and in presenting known results, it is intended that this article be expositoryin nature, providing elementarydemonstrations of some of the central dynamical phenomena and mathematical techniques. It is hoped that the article serves as one possible avenue of entree to the literature on radiallysymmetric solutions of semilinear elliptic problems, especiallyto those articles in which more advanced mathematical theoryis developed. [source] Preface: phys. stat. sol. (c) 1/S2PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue S2 2004E. F. da Silva Jr. The papers in this special issue of physica status solidi (c) are selected manuscripts including diverse research lines presently in development in the ambit of the NanoSemiMat network in Brazil. The 3rd Workshop on Semiconductor Nanodevices and Nanostructured Materials (NanoSemiMat-3) took place in Salvador, Bahia, Brazil, at the Catussaba Resort Hotel, during the period of 24,27 March 2004. The NanoSemiMat network is part of the Brazilian Initiative on Nanoscience and Nanotechnology (N&N), with strategic cooperative research support in this area. The initiative started in 2001, through the formation of four research networks nationwide in different scientific fields associated to NanoScience and Nanotechnology (N&N). The 3rd Workshop on Nanodevices and Nanostructured Materials (NanoSemiMat-3) is an evolution of the two previous meetings which were held in Recife, PE, Brazil and Natal, RN, Brazil in 2002 and 2003, respectively. The meeting comprised 16 invited plenary talks, each 30 minutes long, given by eminent researchers from Brazil, Canada, France, Germany and the United States of America. These invited talks extend through different topics of N&N associated to Nanodevices and Nanostructured Materials: Photodetectors, Lasers and LEDs, Porous Materials, New Materials, and New Technologies, among others. There were short talks presented by representatives of the other N&N networks in Brazil dealing with Molecular Technology and Interfaces, Nanostructured Materials and Nanobiotechnology. Also a poster session, with about 60 presentations, highlighted the main research activities presently being developed by the network members at the different sites which constitute the NanoSemiMat network. The presentations reflected theoretical and experimental research lines which lead to the development of basic and applied research in nanostructured semiconductor materials such as III,V and II,VI, Si and SiC based nanodevices, wide gap materials, ceramics, polymers, porous materials, optical and transport properties of low dimensional structures, magnetic nanostructures and structures under the influence of high fields, spintronics and sensor applications. The participants of the workshop came from 20 research institutions within Brazil and from 7 research laboratories and universities in Europe and North America. In total about 120 researchers, members of the network, invited researchers, representatives of supporting and funding agencies in Brazil, undergraduate and graduate students, technical staff and supporting personal as well as researchers from complementary fields were present. The realization of the NanoSemiMat-3 was possible due to the financial support of the Brazilian Ministry of Science and Technology (MCT) and the Brazilian National Research Council (CNPq) and the logistic support of Federal University of Bahia. All activities during the NanoSemiMat-3 were open to the general public with interest in nanoscience and nanotechnology. In this third workshop of the series, we highlight the expansion of its format, with plenary and invited talks, poster sessions, as well as the presence of seven invited speakers from abroad. We expect that the continuation of the NanoSemiMat series will be a forum for discussions of state-of-the-art research developed in Brazil on N&N and the multidisciplinary field of semiconductor nanodevices and nanostructured materials as well as its superposition to other branches of science. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Statistics-driven Development of OBD Systems: An OverviewQUALITY AND RELIABILITY ENGINEERING INTERNATIONAL, Issue 6 2006Stefano Barone Abstract Automotive on-board diagnostic (OBD) systems are designed to keep critical components under control during vehicle functioning, and to alert the driver in case of severe malfunctions. OBD systems aimed at reducing polluting emissions are mandatory on new motor vehicles. Some research projects conducted in cooperation between universities and the automotive industry have been quite successful in terms of knowledge advancement and industrial gain. An updated overview of the adopted methodologies and results obtained are given in this article. Such results can be valuable for both theorists and practitioners, since they witness the use of statistics as a powerful catalyst of technical progress, and give a possible line of action for further application in several scientific fields. Copyright © 2006 John Wiley & Sons, Ltd. [source] Bioorganic studies on marine natural products,diverse chemical structures and bioactivitiesTHE CHEMICAL RECORD, Issue 5 2006Daisuke Uemura Abstract The discovery of new molecules contributes to the development of basic scientific concepts, leads to valuable drug-oriented compounds, and suggests possible new pharmacological reagents. Newly discovered substances can even be responsible for the creation of new scientific fields. Due to the radically different habitats of marine organisms, several notable examples of secondary metabolites from marine organisms have been isolated. Two of the most remarkable properties of these compounds are their structural and physiological diversities. These bioactive compounds are candidates for drugs or biological probes for physiological studies. Palytoxin is a polyol compound that shows extreme acute toxicity. Halichondrins are remarkable antitumor macrolides from sponge. Pinnatoxins, potent shellfish poisons, cause food poisoning. This paper describes bioorganic studies on such newly discovered wonders of nature. Several bioactive marine alkaloids and important substances involved in dynamic ecological systems are also described. © 2006 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 6: 235,248; 2006: Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/tcr.20087 [source] Impairments on "open-ended" executive function tests in autismAUTISM RESEARCH, Issue 3 2009Sarah J. White Abstract The executive function (EF) theory of autism has received much support recently from a growing number of studies. However, executive impairments have not always been easy to identify consistently and so novel "ecologically valid" tests have been designed which tap into real-life scenarios that are relevant to and representative of everyday behavior. One characteristic of many of these tasks is that they present the participant with an "ill-structured" or "open-ended" situation. Here, we investigated the possibility that tasks with greater degrees of open-endedness might prove more sensitive to detecting executive impairment in autism. Forty-five children with autism spectrum disorder (ASD) were compared to 27 age- and IQ-matched control children on a range of cognitive tests of EF. Group differences were found on half of the tasks, with the greatest degree of impairment detected on the more open-ended tasks. The ASD group also performed more poorly on a simple control condition of a task. Detailed consideration of task performance suggested that the ASD group tended to create fewer spontaneous strategies and exhibit more idiosyncratic behavior, which particularly disadvantaged them on the more open-ended tasks. These kinds of behaviors have been reported in studies of neurological patients with frontal lobe involvement, prima facie suggesting a link between the scientific fields. However, we suggest that this behavior might equally result from a poor understanding of the implicit demands made by the experimenter in open-ended test situations, due to the socio-communicative difficulties of these children. [source] Wissenschaftliche Photographie als visuelle Kultur.BERICHTE ZUR WISSENSCHAFTSGESCHICHTE, Issue 3 2005Die Erforschung und Dokumentation von Spektren Abstract This paper discusses facets of 19th-century scientific photography as a visual culture. The example of spectral research and documentation is particularly well suited, because prismatically diffracted light from the sun or from luminous gases was one of the most frequently examined phenomena of that century. The results were significant not only for physics but also for analytical chemistry and astrophysics. The spectrum also served as an ideal test object for checking the effectiveness of a wide array of photochemically sensitizable surfaces to the various color regions. Scientific photography became the most important experimental technique in the infrared and ultraviolet. H. A. Rowland's spectrum charts are discussed as an example of the transition from comprehensiveness in documentation to fetishism. The discussion of the Lippmann process, one of the first methods of color photography, addresses the associated training of the eye. Issues of authenticity and the much averred ,mechanical objectivity" are raised with regard to retouching. The overriding theme of visual science cultures leads furthermore to unanticipated interdependencies with other scientific fields, such as geography, and draws the importance of practitioners into the foreground. [source] | |||||||||||||||||||